In recent years, spin ice has become a very researchable topic. Thanks to frustrations (or competing interactions) a new physics appears, for the description of which new researches are needed [1]}. Such systems have very rich behavior, but they are difficult to study because of the atomistic scale and three-dimensional lattice [2]}. The researchers attempted to facilitate the task themselves, and try to transferred studies of effects caused by frustrations to more “simple” systems - the artificial spin ice [3]}. Artificial spin ice is an patterned array of nano-islands (macrospins) made of magnetic material disposed on a nonmagnetic substrate and formed into a specific geometry. As Wang wrote in his work “artificial frustrated magnet opens the door to a new mode of research wherein a frustrated system can be designed rather than discovered” [3]}. The main distinctive feature of artificial spin ice from spin ice is that due to its mesoscopic scale and two-dimensionality, both the state of each island and the state of the system as a whole can be investigated using contemporary technologies. The modern development of experimental approaches allows observing static magnetic states of the systems using MFM [3]}, [6]}, [7]}, [8]}, [9]}, it is even possible to observe dynamic magnetic states in real time with X-PEEM [10]} and XMCD-PEEM [11]}, [12]}, [13]}, [14]} methods. Gartside et al. in recent work [15]} showed the “topological defect-driven magnetic writing” method with which one can set the direction of magnetization for each macrospin in the array of artificial spin ice. Thus, with the help of this method, it is now possible to obtain and investigate any magnetic state of such systems.
